الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
Video traffic is currently forming the majority of traffic over Internet. Its percentage is expected to increase in the coming few years. However, a big problem called congestion collapse arises with the increase in the rate of media traffic. Congestion is generally bad for users, applications and Internet performance, and sometimes leads to huge data loss. Congestion control is thus required to prevent congestion collapse in the network. Over years, continuous efforts have been done to solve this problem. TCP-Friendly Rate Control (TFRC) is one of the most promising end-to-end congestion control protocols that handle such problem.
This thesis first investigates the congestion control algorithms. Then, it presents an Enhanced TCP-Friendly Rate Control protocol, called ETFRC, as a means of enhanced congestion control for media traffic over Internet. Three modifications to TFRC are proposed in this thesis so as to develop the ETFRC. The first modification is based on modifying the frequency of the feedback messages sent by TFRC receiver to its sender upon which the sending rate calculation is done. The second modification tackled the number of samples used by the TFRC receiver to calculate the loss event rate as part of the feedback report sent to sender. The third modification is developed by adjusting the sending rate at the sender side dynamically based on the current state of the network and the current state of the receiver. In other words, the ETFRC embodies a new algorithm to tune (increase or decrease) the sending rate at the sender side according to the difference between the calculated rate by the sender and the reported rate from the receiver side. The performance of the proposed ETFRC protocol is evaluated using the network simulator NS2 considering different scenarios. In each scenario, simulated video traffic of the Evalvid framework is sent over the designed topology and different performance parameters are measured and compared with that obtained by applying the original TFRC protocol. The simulation results show that the ETFRC performance surpassed TFRC in terms of throughput, jitter, and packet loss.